[NETFILTER]: Restore {ipt,ip6t,ebt}_LOG compatibility

The nfnetlink_log infrastructure changes broke compatiblity of the LOG
targets. They currently use whatever log backend was registered first,
which means that if ipt_ULOG was loaded first, no messages will be printed
to the ring buffer anymore.

Restore compatiblity by using the old log functions by default and only use
the nf_log backend if the user explicitly said so.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netfilter_bridge/ebt_log.h

@@ -3,6 +3,7 @@
 
 #define EBT_LOG_IP 0x01 /* if the frame is made by ip, log the ip information */
 #define EBT_LOG_ARP 0x02
+#define EBT_LOG_NFLOG 0x04
 #define EBT_LOG_MASK (EBT_LOG_IP | EBT_LOG_ARP)
 #define EBT_LOG_PREFIX_SIZE 30
 #define EBT_LOG_WATCHER "log"

include/linux/netfilter_ipv4/ipt_LOG.h

@@ -6,7 +6,8 @@
 #define IPT_LOG_TCPOPT		0x02	/* Log TCP options */
 #define IPT_LOG_IPOPT		0x04	/* Log IP options */
 #define IPT_LOG_UID		0x08	/* Log UID owning local socket */
-#define IPT_LOG_MASK		0x0f
+#define IPT_LOG_NFLOG		0x10	/* Log using nf_log backend */
+#define IPT_LOG_MASK		0x1f
 
 struct ipt_log_info {
 	unsigned char level;

include/linux/netfilter_ipv6/ip6t_LOG.h

@@ -6,7 +6,8 @@
 #define IP6T_LOG_TCPOPT		0x02	/* Log TCP options */
 #define IP6T_LOG_IPOPT		0x04	/* Log IP options */
 #define IP6T_LOG_UID		0x08	/* Log UID owning local socket */
-#define IP6T_LOG_MASK		0x0f
+#define IP6T_LOG_NFLOG		0x10	/* Log using nf_log backend */
+#define IP6T_LOG_MASK		0x1f
 
 struct ip6t_log_info {
 	unsigned char level;

net/bridge/netfilter/ebt_log.c

@@ -166,7 +166,12 @@ static void ebt_log(const struct sk_buff *skb, unsigned int hooknr,
 	li.u.log.level = info->loglevel;
 	li.u.log.logflags = info->bitmask;
 
-	nf_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li, info->prefix);
+	if (info->bitmask & EBT_LOG_NFLOG)
+		nf_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li,
+		              info->prefix);
+	else
+		ebt_log_packet(PF_BRIDGE, hooknr, skb, in, out, &li,
+		               info->prefix);
 }
 
 static struct ebt_watcher log =

net/ipv4/netfilter/ipt_LOG.c

@@ -425,7 +425,12 @@ ipt_log_target(struct sk_buff **pskb,
 	li.u.log.level = loginfo->level;
 	li.u.log.logflags = loginfo->logflags;
 
-	nf_log_packet(PF_INET, hooknum, *pskb, in, out, &li, loginfo->prefix);
+	if (loginfo->logflags & IPT_LOG_NFLOG)
+		nf_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
+		              loginfo->prefix);
+	else
+		ipt_log_packet(PF_INET, hooknum, *pskb, in, out, &li,
+		               loginfo->prefix);
 
 	return IPT_CONTINUE;
 }

net/ipv6/netfilter/ip6t_LOG.c

@@ -436,7 +436,12 @@ ip6t_log_target(struct sk_buff **pskb,
 	li.u.log.level = loginfo->level;
 	li.u.log.logflags = loginfo->logflags;
 
-	nf_log_packet(PF_INET6, hooknum, *pskb, in, out, &li, loginfo->prefix);
+	if (loginfo->logflags & IP6T_LOG_NFLOG)
+		nf_log_packet(PF_INET6, hooknum, *pskb, in, out, &li,
+		              loginfo->prefix);
+	else
+		ip6t_log_packet(PF_INET6, hooknum, *pskb, in, out, &li,
+		                loginfo->prefix);
 
 	return IP6T_CONTINUE;
 }